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Call for ContributionsHETEROCYCLES Special Issue Vol. 99 in honor of Professor Tohru Fukuyama on 70th Birthday

Submission deadline: September 10, 2018
On the occasion of Professor Tohru Fukuyama's 70th birthday, HETEROCYCLES editorial office is planning to publish special anniversary issue on April 1, 2019 as Vol. 99. Authors are invited to submit their work to this topical issue.
Authors wishing to submit their manuscript should contact editorial office via e-mail by the end of May, 2018. Manuscript should reach the editorial office no later than September 10, 2018.
Contact: submit@heterocycles.com

March 5, 2018

Heterocycles Award
HETEROCYCLES is pleased to announce Heterocycles Award.
In recognition of an outstanding oral presentation at the 47th Congress of Heterocyclic ChemistrySee more

December 13, 2017

Call for ContributionsHETEROCYCLES Special Issue Vol. 97 in honor of Professor Kiyoshi Tomioka on 70th Birthday

Submission deadline: February 15, 2018
On the occasion of Professor Kiyoshi Tomioka's 70th birthday, HETEROCYCLES editorial office is planning to publish special anniversary issue on September 1, 2018 as Vol. 97. Authors are invited to submit their work to this topical issue.
Authors wishing to submit their manuscript should contact editorial office via e-mail by the end of November, 2017. Manuscript should reach the editorial office no later than February 15, 2018.
Contact: submit@heterocycles.com

Abstract

The transition metal-catalyzed intermolecular reaction of carbonyl precursors with alkynes is a simple method for constructing various carbonyl compounds. We review the syntheses of π-conjugated cyclic carbonyl compounds from the reaction of alkynes with suitable carbonyl precursors in the presence of transition metal catalysts. These methods afford isocoumarins, chromones, 2-quinolones, 4-quinolones, and isoquinolones, and the reaction of diynes with carbon dioxide produces pyrones.

Abstract

This review covers reports on the one-electron reductive cyclization reactions affording bicyclic compounds, such as hydrindans, perhydronaphthalenes, perhydroguaianes, and other systems including five-, six-, seven-, and eight-membered carbocycles using SmI2. The substrate is aldehyde, ketone, or ester. The effect of additives, such as H2O, MeOH, HMPA, and NiI2, was studied. The mechanistic aspects recently investigated are also introduced.

■ Synthesis and Antimicrobial Evaluation of Some Isoxazole Based Heterocycles

Abstract

The versatile hitherto unreported 2-cyano-N-(4-{[(5-methylisoxazol-3-yl)amino]sulfonyl}phenyl)acetamide (3) was utilized for the synthesis of a variety of heterocycles incorporating sulfamoyl moiety. The 2-pyridone derivatives were obtained via reaction of cyanoacetamide with pentane-2,4-dione, arylidenes malononitrile, or terephthalaldehyde and malononitrile upon heating under reflux in the presence of a catalyst. Condensation of the cyanoacetamide 3 with salicylaldehyde furnished the corresponding chromene derivatives. Coupling of 3 with arene diazonium chlorides gave the hydrazone derivatives 13a-c, which upon treatment with hydrazine hydrate and ethyl chloroformate furnished the corresponding pyrazole and triazine derivatives, respectively. Reaction of 3 with carbon disulfide and 1,2-dibromoethane, 1,3-dibromopropane or dimethyl sulfate afforded 2-cyano-2-(1,3-dithiolan-2-ylidene)-N-(4-{[(5-methylisoxazol-3-yl)amino]sulfonyl}phenyl)acetamide (18), 2-cyano-2-(1,3-dithian-2-ylidene)-N-4-{[(5-methylisoxazol-3-yl)amino]sulfonyl}phenyl)acetamide (19), and 2-cyano-N-(4-{[(5-methylisoxazol-3-yl)amino]sulfonyl}phenyl)-3,3-bis(methylthio)acrylamide (20). The newly synthesized compounds were evaluated for their in vitro antibacterial and antifungal activities, and showed promising results.

Abstract

The facile procedure for the synthesis of the 11H-pyrido[3,2-a]carbazole structure involving the Fischer indole cyclization on tetrahydroquinolinones, available from enaminones and methyl 2-formyl-3-oxopropanoate, followed by the aromatization of the resulting 5,6-dihydro derivatives is described. This method allows for the introduction of substituents at C2, C6, and C8 to the scaffold by choice of the starting materials. In the biological testing, introduction of the phenyl group at C6 is significantly effective to improve the antiproliferative activity.

Abstract

A novel and efficient route to benzoxazoles and oxazolines involving a nickel-catalyzed three-component coupling reaction of iodobenzene, an amino alcohol and tert-butyl isocyanide has been developed. A wide array of products have been prepared in good to excellent yields in the absence of ligand.

■ A New Flavonoid Glycoside and Four Other Chemical Constituents from Viscum coloratum and Their Antioxidant Activity

Abstract

A new flavonoid glycoside, identified as rhamnazin-3-Ο-β-D-(6′′-β-hydroxy-β-methylglutaryl)-β-D-glucoside-4′-Ο-β-D-glucoside (1), along with four known compounds, shikimic acid (2), quebrachitol (3), abscisic acid (4), 3,5-dihydroxy-1,7-bis(4-hydroxyphenyl)heptane (5), were isolated from the branches and leaves of Viscum coloratum. Their structures were elucidated on the basis of MS, 1D NMR, and 2D NMR techniques. All compounds were isolated in the family Loranthaceae for the first time. This paper describes the isolation, structural elucidation as well as in vitro antioxidant activity of these isolates.

■ A Facile Synthesis and Ring-Opening Reactions of Novel 2-Ferrocenyl-3,4-dihydropyrans

Abstract

A series of novel 2-ferrocenyl-3,4-dihydropyrans were synthesized in good to excellent yields through three-component reaction of vinylferrocene, 1,3-dicarbonyl compound and formaldehyde near room temperature under catalyst-free conditions. The obtained ferrocenyl dihydropyrans can also react readily with indole in the presence of alum, providing a ring-opening product in high yield, and this result opens an effective way to access a new class of complex ferrocenyl derivatives.

Abstract

3-Acetylisoxazoles were synthesized by the reaction of alkenes or alkynes in acetone as solvent with copper(II) nitrate and formic acid. In the case of ethyl acetate as solvent, 3-benzoylisoxazoles were yielded by the reaction of alkynes and acetophenone with copper(II) nitrate and nitric acid. This synthetic method provides a convenient production of isoxazole derivatives.

■ An Efficient One-Pot Synthesis of Some New Substituted 1,2,3,5-Thiatriazolidin-4-one 1,1-Dioxides

Abstract

A series of some new 1,2,3,5-thiatriazolidin-4-one 1,1-dioxides derivatives were synthesized by reacting respectively β-cyanohydrazines and phosphorylated hydrazine with chlorosulfonyl isocyanate in good yields. The structures of all the newly prepared compounds were confirmed by IR, 1H, 13C, 31P-NMR spectral data and elemental analysis.

Abstract

An efficient method for the preparation of 4-alkoxy-substituted thieno[2,3-b]pyridines is described. The key intermediates, 4-alkoxy-2-chloro-3-cyanopyridines, were synthesized from a variety of alcohols by nucleophilic substitution with 3-cyano-2,4-dichloropyridine or by Mitsunobu reaction with 2-chloro-4-hydroxynicotinonitrile. Subsequent reaction of 4-alkoxy-2-chloro-3-cyanopyridines with 2-(acetylthio)acetamide under basic conditions provided 4-alkoxy-substituted thieno[2,3-b]pyridines in fair to good yields.

Abstract

(E)-3-(2-Hydroxynaphthalen-1-yl)propenoyl- and (E)-3-(2-hydroxynaphthalen-1-yl)-2-methylpropenoyl-protected aliphatic and aromatic primary amines were synthesized and their photolytic behavior in methanol was explored. The results showed that irradiation of the hydroxynaphthyl-propenamide derivatives in a protic polar solvent at wavelengths greater than 280 nm or 340 nm causes rather efficient deprotection reactions to afford the desired amines quantitatively along with fluorescent benzocoumarins.